drm/i915/icl: Define MOCS table for Icelake

The table has been unified across OSes to minimize virtualization overhead.

The MOCS table is now published as part of bspec, and versioned. Entries
are supposed to never be modified, but new ones can be added. Adding
entries increases table version. The patch includes version 1 entries.

Meaning of each entry is now explained in bspec, and user mode clients
are expected to know what each entry means. The 3 entries used for previous
platforms are still compatible with their legacy definitions, but that is
not guaranteed to be true for future platforms.

v2: Fixed SCC values, improved commit comment (Daniele)
v3: Improved MOCS table comment (Daniele)
v4: Moved new entries below gen9 ones. Put common entries into
    definition to be used in multiple arrays. (Lucas)
v5: Made defines for or-ing flags. Renamed macros from MOCS_TABLE
    to MOCS_ENTRIES. Switched LE_CoS to upper case. (Joonas)
v6: Removed definitions of reserved entries. (Michal)
    Increased limit of entries sent to the hardware on gen11+.
v7: Simplify table as done for previou gens (Lucas)
v8: Rebase on cached number of entries per-platform and use new
    MOCS_ENTRY() macro (Lucas)
v9: Update comment (from Tomasz)

BSpec: 34007
BSpec: 560
Signed-off-by: Tomasz Lis <tomasz.lis@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190124000604.18861-8-lucas.demarchi@intel.com

drivers/gpu/drm/i915/intel_mocs.c

@@ -46,6 +46,8 @@ struct drm_i915_mocs_table {
 #define LE_SCC(value)		((value) << 8)
 #define LE_PFM(value)		((value) << 11)
 #define LE_SCF(value)		((value) << 14)
+#define LE_COS(value)		((value) << 15)
+#define LE_SSE(value)		((value) << 17)
 
 /* Defines for the tables (LNCFMOCS0 - LNCFMOCS31) - two entries per word */
 #define L3_ESC(value)		((value) << 0)
@@ -54,6 +56,7 @@ struct drm_i915_mocs_table {
 
 /* Helper defines */
 #define GEN9_NUM_MOCS_ENTRIES	62  /* 62 out of 64 - 63 & 64 are reserved. */
+#define GEN11_NUM_MOCS_ENTRIES	64  /* 63-64 are reserved, but configured. */
 
 /* (e)LLC caching options */
 #define LE_0_PAGETABLE		_LE_CACHEABILITY(0)
@@ -89,18 +92,23 @@ struct drm_i915_mocs_table {
  * LNCFCMOCS0 - LNCFCMOCS32 registers.
  *
  * These tables are intended to be kept reasonably consistent across
- * platforms. However some of the fields are not applicable to all of
- * them.
+ * HW platforms, and for ICL+, be identical across OSes. To achieve
+ * that, for Icelake and above, list of entries is published as part
+ * of bspec.
  *
  * Entries not part of the following tables are undefined as far as
  * userspace is concerned and shouldn't be relied upon.  For the time
  * being they will be initialized to PTE.
  *
- * NOTE: These tables MUST start with being uncached and the length
- *       MUST be less than 63 as the last two registers are reserved
- *       by the hardware.  These tables are part of the kernel ABI and
- *       may only be updated incrementally by adding entries at the
- *       end.
+ * The last two entries are reserved by the hardware. For ICL+ they
+ * should be initialized according to bspec and never used, for older
+ * platforms they should never be written to.
+ *
+ * NOTE: These tables are part of bspec and defined as part of hardware
+ *       interface for ICL+. For older platforms, they are part of kernel
+ *       ABI. It is expected that, for specific hardware platform, existing
+ *       entries will remain constant and the table will only be updated by
+ *       adding new entries, filling unused positions.
  */
 #define GEN9_MOCS_ENTRIES \
 	MOCS_ENTRY(I915_MOCS_UNCACHED, \
@@ -125,6 +133,108 @@ static const struct drm_i915_mocs_entry broxton_mocs_table[] = {
 		   L3_3_WB)
 };
 
+#define GEN11_MOCS_ENTRIES \
+	/* Base - Uncached (Deprecated) */ \
+	MOCS_ENTRY(I915_MOCS_UNCACHED, \
+		   LE_1_UC | LE_TC_1_LLC, \
+		   L3_1_UC), \
+	/* Base - L3 + LeCC:PAT (Deprecated) */ \
+	MOCS_ENTRY(I915_MOCS_PTE, \
+		   LE_0_PAGETABLE | LE_TC_1_LLC, \
+		   L3_3_WB), \
+	/* Base - L3 + LLC */ \
+	MOCS_ENTRY(2, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(3), \
+		   L3_3_WB), \
+	/* Base - Uncached */ \
+	MOCS_ENTRY(3, \
+		   LE_1_UC | LE_TC_1_LLC, \
+		   L3_1_UC), \
+	/* Base - L3 */ \
+	MOCS_ENTRY(4, \
+		   LE_1_UC | LE_TC_1_LLC, \
+		   L3_3_WB), \
+	/* Base - LLC */ \
+	MOCS_ENTRY(5, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(3), \
+		   L3_1_UC), \
+	/* Age 0 - LLC */ \
+	MOCS_ENTRY(6, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(1), \
+		   L3_1_UC), \
+	/* Age 0 - L3 + LLC */ \
+	MOCS_ENTRY(7, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(1), \
+		   L3_3_WB), \
+	/* Age: Don't Chg. - LLC */ \
+	MOCS_ENTRY(8, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(2), \
+		   L3_1_UC), \
+	/* Age: Don't Chg. - L3 + LLC */ \
+	MOCS_ENTRY(9, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(2), \
+		   L3_3_WB), \
+	/* No AOM - LLC */ \
+	MOCS_ENTRY(10, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(3) | LE_AOM(1), \
+		   L3_1_UC), \
+	/* No AOM - L3 + LLC */ \
+	MOCS_ENTRY(11, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(3) | LE_AOM(1), \
+		   L3_3_WB), \
+	/* No AOM; Age 0 - LLC */ \
+	MOCS_ENTRY(12, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(1) | LE_AOM(1), \
+		   L3_1_UC), \
+	/* No AOM; Age 0 - L3 + LLC */ \
+	MOCS_ENTRY(13, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(1) | LE_AOM(1), \
+		   L3_3_WB), \
+	/* No AOM; Age:DC - LLC */ \
+	MOCS_ENTRY(14, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(2) | LE_AOM(1), \
+		   L3_1_UC), \
+	/* No AOM; Age:DC - L3 + LLC */ \
+	MOCS_ENTRY(15, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(2) | LE_AOM(1), \
+		   L3_3_WB), \
+	/* Self-Snoop - L3 + LLC */ \
+	MOCS_ENTRY(18, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(3) | LE_SSE(3), \
+		   L3_3_WB), \
+	/* Skip Caching - L3 + LLC(12.5%) */ \
+	MOCS_ENTRY(19, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(3) | LE_SCC(7), \
+		   L3_3_WB), \
+	/* Skip Caching - L3 + LLC(25%) */ \
+	MOCS_ENTRY(20, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(3) | LE_SCC(3), \
+		   L3_3_WB), \
+	/* Skip Caching - L3 + LLC(50%) */ \
+	MOCS_ENTRY(21, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(3) | LE_SCC(1), \
+		   L3_3_WB), \
+	/* Skip Caching - L3 + LLC(75%) */ \
+	MOCS_ENTRY(22, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(3) | LE_RSC(1) | LE_SCC(3), \
+		   L3_3_WB), \
+	/* Skip Caching - L3 + LLC(87.5%) */ \
+	MOCS_ENTRY(23, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(3) | LE_RSC(1) | LE_SCC(7), \
+		   L3_3_WB), \
+	/* HW Reserved - SW program but never use */ \
+	MOCS_ENTRY(62, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(3), \
+		   L3_1_UC), \
+	/* HW Reserved - SW program but never use */ \
+	MOCS_ENTRY(63, \
+		   LE_3_WB | LE_TC_1_LLC | LE_LRUM(3), \
+		   L3_1_UC)
+
+static const struct drm_i915_mocs_entry icelake_mocs_table[] = {
+	GEN11_MOCS_ENTRIES
+};
+
 /**
  * get_mocs_settings()
  * @dev_priv:	i915 device.
@@ -142,8 +252,12 @@ static bool get_mocs_settings(struct drm_i915_private *dev_priv,
 {
 	bool result = false;
 
-	if (IS_GEN9_BC(dev_priv) || IS_CANNONLAKE(dev_priv) ||
-	    IS_ICELAKE(dev_priv)) {
+	if (IS_ICELAKE(dev_priv)) {
+		table->size  = ARRAY_SIZE(icelake_mocs_table);
+		table->table = icelake_mocs_table;
+		table->n_entries = GEN11_NUM_MOCS_ENTRIES;
+		result = true;
+	} else if (IS_GEN9_BC(dev_priv) || IS_CANNONLAKE(dev_priv)) {
 		table->size  = ARRAY_SIZE(skylake_mocs_table);
 		table->n_entries = GEN9_NUM_MOCS_ENTRIES;
 		table->table = skylake_mocs_table;